Insomnia, the most common sleep disorder, affects approximately 50-70 million American adults. It is characterized by difficulty falling asleep, waking frequently during the night, waking too early and not being able to return to sleep, or waking up and not feeling refreshed.
Early treatments for insomnia commonly employed central nervous system (CNS) depressants such as barbiturates. These compounds typically have long half lives and have a well-known spectrum of side effects, including lethargy, confusion, depression and next day hangover effects. In addition, chronic use has been associated with a high potential for addiction involving both physical and psychological dependence. Treatments moved away from barbiturates and other CNS depressants toward the benzodiazepine class of sedative-hypnotic agents. This class of compounds produces a calming effect that results in a sleep-like state in patients and animals, with a greater safety margin than prior hypnotics. However, many benzodiazepines possess side effects that limit their usefulness in certain patient populations. These problems include synergy with other CNS depressants (especially alcohol), the development of tolerance upon repeat dosing, rebound insomnia following discontinuation of dosing, hangover effects the next day and impairment of psychomotor performance and memory. More recent treatments for insomnia have used non-benzodiazepine compounds. Ambien (zolpidem), Sonata (zaleplon) are examples of approved drug products. A need exists in the art for safe and therapeutically effective non-benzodiazepine agents for treating sleep disorders.
Night Eating Syndrome (NES) is generally associated with insufficient food intake in the first half of the day, evening hyperphagia and then insomnia and also sleep awakenings. See, e.g., Vander Wal, Jillon S., Clinical Psychology Review (2012) 32(1), 49-59. Despite increased awareness of NES, it is still not recognized, and more importantly, approaches to treatment continue to be investigated without success.
The present invention relates to the use of ghrelin receptor inverse agonists or antagonists for treating sleep disorders.